Radiator siphon trap



Jam 4, 1938. E. N. GROGAN RADIATOR SIPHON TRAP Filed Nov. 11, 19562Sheets Sheet l in Denier Attorneys Jan. 4: 193% E. N GROGAN RADIATORSIPHON TRAP 2 Sheets-Sheet 2 A5 7! "gap g/3% a ay W Attorneys PatentedJan. 4, 1938 UNITED STATES PATENT OFFICE 3 Claims.

This invention relates to valves and more particularly to what is knownin the art as low pressure steam traps for use on radiator return linesof heating systems.

An object of the present invention is to provide a siphon trap forradiators for economically taking care of condensation and consequentlyreduce fuel cost, increase boiler efiiciency and to reduce maintenancecost.

A further object of the invention is to provide a radiator siphon trapwhich will insure a return of the products of condensation to theheating unit at a temperature higher than is now realized in the typesof traps presently used, and whereby this result is obtained withoutadditional loss of heat units in the radiator.

The invention together with its objects and advantages will be bestunderstood from a study of the following description taken in connectionwith the accompanying drawings wherein:--

Figure 1 is an elevational view illustrating the application of thetrap.

Figure 2 is an enlarged detail view with parts broken away and shown insection illustrating the trap.

Figure 3 is an enlarged detail sectional view of the valve assemblyportion of the trap.

Figure 4 is a sectional view through a valve seat and Figure 5 is abottom plan view of the valve seat.

Figure 6 is a sectional view through a primary valve stem and Figure '7is a sectional view through a secondary valve tube.

Referring more in detail to the drawings it will be seen that theinvention, which latter is adapted for use on the radiator of a heatingsystem between the outlet or return 5 of the radiator 8 and the returnline I, comprises a casing or hous- 40 ing 8 which is of conventionaland well known construction and has its inlet side suitably coupled withthe radiator outlet 5 as at 9 and its bottom outlet suitably coupledwith the return pipe T as at I0.

Arranged within the housing or casing 8 is a thermostat I I having aninternally threaded socket or pin extension I2 associated therewith asclearly shown in Figure 2.

In accordance with the present invention there is provided above theoutlet ll] of the valve casing a threaded bore I3 into which is screweda valve seat member I4 the head of which is diametrically enlarged toengage the inner end of the bore I3 as at I5.

The seat I4 is provided at the center thereof with a hollow socket-likeportion I6 from which extend inclined radial passages I'I, while at theinner or lower end of the hollow or socket I6 the valve seat I4 isinternally threaded as at I8.

A secondary valve tube I9 in the form of a tube open at one end isprovided, and said secondary valve tube III at the open end thereof isthreaded asat for screw threaded engagement with the threaded apertureI8 of the seat I4. Adjacent its closed end the secondary valve tube I9is provided with a bore H.

A primary valve stem 22 has an enlarged threaded end 23 that is screwedinto the socket or pin extension I2 of the thermostat II while for themajor portion of the length thereof the primary valve stem 22 isprovided with a bore 24 that opens at the free end of the stem andslidably accommodates the secondary valve tube I9 as shown in Figure 2.

Intermediate its ends the primary valve stem 22 is provided with ashoulder 25 that is adapted to engage the seat I4 when the thermostat IIis expanded in a manner to prevent the escape of steam from theradiators.

Above the shoulder 25 the primary valve stem 22 is provided with a port26 that is adapted to align with the port 2| of the secondary valve tubeI9 when shoulder 25 is seated against the seat 24. Thus it will be seenthat while the escape of steam from the radiator is effectivelyprevented the products of condensation will pass through the alignedports 2I and 26 and through the secondary valve tube I9 to the returnline I.

When, however, the temperature of the radiator falls a material degree,the thermostat II will contract for unseating the valve 22 permitting afree flow of the steam and water through the trap to the return line I,the water then passing down through the hollow I6 and passages IT to thereturn line I. It will be seen that as the seat I4 or the shoulder 25wears valve stem 22 may be readily adjusted relative to the pin I2.

In connection with the above it will be appreciated that when theradiator is cold and filled with air valve 22 is in the position shownin Figure 2. The admission of steam through the radiator will force thecold air from the radiator out through the trap, the cold air passingthrough the ports I! and into the return pipe, it being noted that anywater which might tend to collect in the radiator will have previouslydrained out from the radiator through the ports II. As the steam entersthe radiator and warms the same air is forced from the radiator throughthe trap and out through the return pipe connected with the trap.However, as soon as steam begins to pass the thermostat H will begin toexpand so that valve 22 is lowered to engage the shoulder 25 thereofwith the seat I4 whereupon steam cannot pass through the trap.

Upon the aforementioned seating of valve 22 port 26 will aline with port2!. These ports 26, 2| are minute so that when the ports are alined nomaterial amount of live steam will escape therethrough, although theports are of such a size as to permit a free escape of air andcondensate. In this connection it will be further appreciated that theconstruction of the thermostat H is such as to provide a sensitivecontrol, allowing water and air to pass freely, but preventing anyappreciable amount of steam from passing until valve' 22 has movedupwardly in response to the contraction of the thermostat H a materialdistance from its seat M. In this connection it will be furtherappreciated that any slight contraction of the thermostat ll will tendto raise the valve element 22 so as to move the port 26 out of alinementwith the port 2i, permitting, when the radiator cools, the escape of airand water at a more rapid rate and consequently live steam will morequickly enter the radiator from the inlet side thereof to the end that aconstant, or only slightly variant temperature will be maintained withinthe radiator.

An advantage, as obtained by this valve, of permitting a constant escapeof air and condensate without a material escape of steam is that theradiator is substantially at all times filled with live steam, when thesystem is in operation, the escape of condensate from the radiator beingpermitted approximately at the rate at which it is formed.

To lock the valve stem 22 and the pin l2 against axial separation, saidpin I2 is provided at diametrically opposite sides thereof with openingswhich align with a slot or opening 26 to receive a cotter pin or thelike 21.

It is thought that a clear understanding of the construction, utilityand advantages and the operation of the invention will be had without amore detailed description thereof.

Having thus described the invention, what is claimed is:

1. A low pressure steam trap including a casing having an inlet neckadapted to be coupled with the outlet of a radiator and an outlet neckadapted to be coupled with the return line of a heating system, saidcasing having a thermostat arranged therein and provided with aninternally threaded pin, a valve seat removably secured within thecasing in line with the outlet of the casing, the valve seat beingprovided with an axial socket opening at the top of the seat and with athreaded opening concentric to the socket and opening through the bottomof the seat, a secondary valve tube disposed axially of the seat, saidtube being closed at one end and open at its other end, and at said lastmentioned end being externally threaded for threaded engagement withinthe threaded opening of the valve seat, said tube adjacent the closedend thereof being also provided with a lateral port, and a valve stemhaving a sliding fit on the secondary valve tube and having a threadedend screw threadedly engaged with the pin of the thermostat, said valvestem intermediate its ends being provided with a shoulder adapted, uponexpansion of the thermostat, to engage said seat, and said valve stemabove said shoulder being provided with a port to align with the port inthe secondary valve tube when said shoulder is engaged with the seatwhereby to provide for an even flow of water from the radiator throughthe trap and into the return line of the heating system when saidshoulder is engaged with the valve seat.

2. A low pressure steam strap including a casing having an inlet neckadapted to be coupled with the outlet of a radiator and an outlet neckadapted to be coupled with the return line of a heating system, saidcasing having a thermostat arranged therein and provided with aninternally threaded pin, a valve seat removably secured within thecasing in line with the outlet of the casing, the valve seat beingprovided with an axial socket opening at the top of the seat and with athreaded opening concentric to the socket and opening through the bottomof the seat, a secondary valve tube disposed axially of the seat, saidtube being closed at one end and open at its other end, and at said lastmentioned end being externally threaded for threaded engagement withinthe threaded opening of the valve seat, said tube adjacent the closedend thereof being also provided with a lateral port, and a valve stemhaving a sliding fit on the secondary valve tube and having a threadedend screw threadedly engaged with the pin of the thermostat, said valvestem intermediate its ends being provided with a shoulder adapted, uponexpansion of the thermostat, to engage said seat, and said valve stemabove said shoulder being provided with a port to align with the port inthe secondary valve tube when said shoulder is engaged with the seatwhereby to provide for an even flow of water from the radiator throughthe trap and into the return line of the heating system when saidshoulder is engaged with the valve seat, and said valve seat upwardlyfrom its bottom end being provided with radial ports through which steampasses from the trap when the shoulder of the valve stem is in raisedposition out of engagement with said valve seat.

3. In a valve of the character described, a valve seat provided with anaxial socket opening at the top of the seat and a threaded opening atthe bottom of the seat, a secondary valve tube having an open endexternally threaded and threadedly engaged in the opening of the valveseat, said tube being closed at its opposite end and provided adjacentsaid opposite end with a lateral minute intake opening, and a valve stemhaving a sliding fit on said secondary valve tube, said valve stemhaving a diametrically enlarged portion to engage with said seat, andalso having a lateral minute port'aligning with the port in thesecondary valve tube when the valve stem is in seated position.

EDGAR N. GROGAN.

